Electronic mail (e-mail) has been commonly used as a useful advertising tool for many people or companies to post advertising message in bulk to different users in different countries and regions, consequently, a computer user will probably be harassed by hundreds of advertising e-mails (which is also called junk mail) every day.
Many efforts have been made in many countries and regions to develop a method of technologically blocking junk mail, or make a law on prevention of abuse of junk mail.
Facing the new junk-mail blocking technology and the new law on prevention of abuse of junk mail, the advertising-mail senders also fear that their survival will be affected if the advertising e-mail can not be mailed anymore.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages.